1. Field of the Invention
The present invention relates to a cam apparatus for performing processing such as punching, bending, and the like with respect to a workpiece such as a thin plate by means of a tool fitted to a cam slide by causing the cam slide to slide by a cam driver.
2. Description of the Related Art
A cam apparatus of a suspended cam type, for example, generally comprises a cam driver which is adapted to be fixedly supported by a cam-driver supporting base; a cam slide having a sliding surface with a shape complementary to the sliding surface of the cam driver so as to movably contact that sliding surface; a cam-slide supporting base for movably suspending and supporting the cam slide so that the cam slide can move while being guided by the sliding surface of the cam driver as the sliding surface of the cam slide and the sliding surface of the cam driver are brought into contact with each other; and a returning mechanism having a coil spring for generating a returning force for returning the cam slide to its initial position.
In such a cam apparatus of the suspended cam type, at the time of performing the operation of adjusting and confirming the position of a tip of an edge tool in the state of a bottom dead center, the operation of removing the coil spring which generates a large returning force in the state of the bottom dead center is normally effected in advance so as to facilitate the operation of the position adjustment and confirmation.
Incidentally, the above-described operation of removing the coil spring involves the operation of dismounting and mounting the cam slide with respect to the cam-slide supporting base. Moreover, after the operation of the position adjustment and confirmation, the operation of dismounting and mounting the cam slide with respect to the cam-slide supporting base is required again to fit the coil spring.
In addition, the above-described troublesome operation is required also in the maintenance, inspection, and replacement of the coil spring in the cam apparatus which involves the operation of dismounting and mounting the cam slide with respect to the cam-slide supporting base for the operation of removing the coil spring in the operation of adjusting and confirming the position of the tip of the edge tool in the state of the bottom dead center.
It should be noted that such a drawback does not occur only in the cam apparatus of the suspended cam type, but similarly occurs in the cam apparatus of the lower mounted type as well.